Organic infill for artificial turf fields

ABSTRACT

The present invention relates to organic infill for artificial turf fields. The organic infill includes at least one layer of particles having walnut shell particles. At least 1% of the walnut shell particles are particles that have a sieve size of 50 or smaller sized particles. The at least one layer can further include walnut shell particles in other sieve ranges, sand, or both, and be intermixed in the at least one layer. The organic infill can also include a layer of sand overlaying a backing of an artificial turf field. The at least one layer overlays on the sand layer. The organic infill can further include a layer of walnut shell particles or extruded composite. The layer includes walnut shell particles having a sieve range different from the sieve range in the at least one layer. The layer overlays on the at least one layer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application 62/397,295, filed on Sep. 20, 2016, the entirety of which is herein incorporated by reference.

FIELD OF THE INVENTION

Embodiments of the present invention relate to organic infill for artificial turf fields. More particularly, the embodiments relate to organic infill comprising walnut shell particles.

BACKGROUND OF INVENTION

There is currently a potential trend and related search with respect to new infill materials and compositions for artificial turf fields. A particular focus has been towards developing an infill that uses organic materials. For example, some customers of infill materials have sought to reduce or eliminate the use of certain compounds such as recycled rubber for the infill of their artificial turf fields.

As a matter of background, a significant amount of engineering and development is devoted to developing artificial turf field systems. With respect to the infill, each kind of material often times has its own performance and structural characteristics. Obtaining the right composition and arrangement of materials can be challenging.

SUMMARY OF THE INVENTION

In accordance with principles of the present invention, an infill composition for artificial turf fields is contemplated. In one embodiment, the infill composition comprises at least one layer of particles comprising walnut shell particles. The walnut shell particles include walnut particles that have a sieve size of 50 or smaller sized particles. The walnut particles that have a sieve size of 50 or smaller sized particles are between about 1% and about 5% by weight of the walnut shell particles.

In one embodiment, the at least one layer is applied over a backing of an artificial turf field and is interspersed between artificial fibers.

In one embodiment, the infill is an organic infill that is without or is almost entirely without containing rubber or similar materials.

In one embodiment, the remainder of the walnut shell particles in the layer includes an amount of walnut shell particles in the 10-40 sieve range. The amount of walnut shell particles in the 10-40 sieve range is 50% or higher by weight of the walnut shell particles.

In one embodiment, the at least one layer is made entirely from walnut shell particles.

In one embodiment, the walnut shell particles are raw or untreated crushed walnut shells.

In one embodiment, the walnut shell particles further comprise walnut shell particles in a first sieve range. The walnut shell particles in the first sieve range include walnut shell particles larger than the particles having a sieve size of 50 or smaller.

In one embodiment, the amount of the walnut shell particles in the first sieve range is above 90% by weight of the walnut shell particles. The first sieve range may be from 14 to 40. The walnut shell particles in the first sieve range and the particles between about 1% and about 5% by weight of the walnut shell particles may be intermixed in the at least one layer. The at least one layer of particles may further comprise sand. The particles between about 1% and about 5% by weight of the walnut shell particles, the walnut shell particles in the first sieve range, and the sand may be intermixed in the at least one layer of particles.

In one embodiment, the particles between about 1% and about 5% by weight of the walnut shell particles are particles that have a sieve size from 50 to 100.

In one embodiment, the at least one layer of particles further comprises sand in a sieve size range from 20 to 50. The walnut shell particles and the sand may be intermixed in the at least one layer.

In one embodiment, the infill composition further comprises a second layer of particles including sand overlaying a backing of an artificial turf field. The least one layer overlays the second layer. The infill composition may further comprises a third layer of walnut shell particles or extrude composite, and the third layer overlays the least one layer. The walnut shell particles further comprise walnut shell particles in a first sieve range. The walnut shell particles in the first sieve range may include walnut shell particles larger than the particles having a sieve size of 50 or smaller The walnut shell particles in the third layer may be in a second sieve range that is different from the first sieve range.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 depicts illustrative infill having a layer of crushed shells that includes a combination of large and fine walnut shell particles in accordance with some embodiments of the present invention;

FIG. 2 depicts illustrative infill comprising fine walnut shell particles and sand in separate layers in accordance with some embodiments of the present invention;

FIG. 3 depicts illustrative infill comprising a layer of fine walnut shell particles and sand intermixed in accordance with sonic embodiments of the present invention;

FIG. 4 depicts illustrative infill comprising a layer of sand and a layer of walnut shell particles of two different particle size ranges in accordance with some embodiments of the present invention;

FIG. 5 depicts illustrative infill comprising a first layer of sand and a second layer of walnut shell particles and sand in accordance with some embodiments of the present invention;

FIG. 6 depicts the infill in FIG. 5 further comprising a third layer of walnut shell particles or extruded composite in accordance with some embodiments of the present invention;

FIG. 7 depicts illustrative infill comprising a first layer of sand, a second layer of walnut shell particles and sand, and a third layer of extruded composite in accordance with some embodiments of the present invention; and

FIG. 8 provides an illustrative particle size distribution for crushed walnut shell particles for use in a layer above the sand layer in accordance with some embodiments of the present invention.

The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, all illustrations are intended to convey concepts, where relative sizes, shapes and other detailed attributes may be illustrated. schematically rather than literally or precisely.

DETAILED DESCRIPTION OF THE INVENTION

In accordance with principles of the present invention, embodiments of the present invention are directed to using crushed walnut shells as a primary portion of the infill for an artificial turf field. Infill, as shown in FIG. 1, refers to material that is deposited over the turf backing 120 and forms a layer 105 around the turf fibers 125. Infill is interspersed between the turf fibers 125 rising out of the turf backing 120. Infill generally has a depth that covers a portion of the turf fiber (unexposed portion of the turf fiber) leaving part of the turf fiber extending above the infill (exposed portion of the turf fiber). Infill helps support the turf fibers 125 in an upright position and is used to provide traction and shock absorption. In some embodiments, the infill 105 comprises a layer of crushed shells that include a combination of large 110 and fine 115 walnut shell particles and in particular, the walnut shell particles (in the infill) include fine walnut shell particles 115 that have particle sizes that are 0.595 mm and lower, preferably 0.420 mm and lower, more preferably lower than 0.297, and even more preferably lower than 0.297 and higher than or equal to 0.149 mm. Preferably, these fine walnut shell particles 115 are at least 1.0% (and no more than 10% or preferably no more than 5%) by weight of the crushed shells in that layer and the large walnut shell particles 110 are also contained in that layer such as by containing about 50% by weight of the crushed shells or preferably above 90% by weight of the crushed shells. In some embodiments, the infill 105 when installed comprises a layer of crushed shells that consists essentially of large 100 and fine 115 walnut shell particles, wherein at least 1% (and no more than 10% or preferably no more than 5%) by weight of the crushed shells in that layer are particles that have a seize size of 50 or smaller size particles. From initial testing, it has been found that including the fine walnut shell particles in combination with the larger walnut shell particles provides improved performance athletic fields, namely a more stable surface, providing better foot stability and playability. In application, a composition of crushed walnut shells is prepared and delivered to a field for installation. The composition of the walnut shells is provided to have the illustrative particle size and percentage weight characteristics that are described in or understood from the disclosure herein. Thus, it would for example provide one of the source materials that are used in installing the infill on the field.

As a general matter, various types of infill arrangements are contemplated. For example, two layer, three layers, or other arrangements are contemplated. For convenience, the present description primarily discusses two and three layer embodiments. Embodiments of the present invention are directed to providing organic infill solutions. The materials that are discussed are primarily sand and crushed walnut shells but it should be understood that other materials can be included or substituted. In some embodiments, the infill material is directed to having the crushed walnut shells, in effect, replace crumb rubber infill materials. As such, the infill is devoid or substantially devoid of crumb rubber or similar materials. For example, in such embodiments, one layer of the infill (e.g., one of the multiple layers in the infill) can be made entirely (100% by weight), substantially (e.g., 65% or higher or 75% or higher by weight), primarily (e.g., 50% or higher by weight), or predominantly (e.g., 45% or higher by weight, or a percentage by weight that is higher than the percentage by weight of any other particle or sand in the same layer) of the crushed walnut particles. In sonic embodiments, that layer when installed can consist essentially of the crushed walnut particles, wherein at least 1% (and no more than 10% or preferably no more than 5%) by weight of the crushed walnut particles in that layer are particles that have a seize size of 50 or smaller size particles. In some embodiments, the infill can be only one layer, and the only layer can be made entirely (100% by weight), substantially (e.g., 65% or higher or 75% or higher by weight), primarily (e.g., 50% or higher by weight), or predominantly (e.g., 45% or higher by weight, or a percentage by weight that is higher than the percentage by weight of any other particle or sand in the layer) of the crushed walnut particles. In some embodiments, the only one layer when installed can consist essentially of the crushed walnut particles, wherein at least 1% (and no more than 10% or preferably no more than 5%) by weight of the crushed walnut particles in that layer are particles that have a seize size of 50 or smaller size particles. The walnut shells can provide shock absorbency and traction. It is possible for the infill layer to include other organic materials or other materials.

The following description provides a number of examples of embodiments of the present invention.

The infill may include or comprise fine walnut shell particles in a particular size range (e.g., as specified by a range of sieve-sizes). The range of sieve-sizes may be from 30 to 200 (i.e., 0.595 mm-0.074 mm), and preferably 50 to 100 (i.e., 0.297 mm-0.149 mm). In some embodiments, the infill may comprise sand (e.g., in a layer) that is in a particular size range. The range of sieve-sizes for sand may be from 20 to 50 (i.e., 0.841 mm-0.297 mm). The infill may comprise the aforementioned fine walnut shell particles and sand in separate layers (one overlaying the other) or they are preferably intermixed as shown in FIGS. 2-3. FIG. 2 depicts illustrative infill 205 comprising fine walnut shell particles and sand in separate layers. The first layer 210 (sequentially in the order of layers from bottom to top, where bottom is closest to the ground) is preferably a sand layer. In a second layer 215, the infill may comprise fine particles. The second layer 215 may comprise the aforementioned fine walnut shell particles, the aforementioned fine sand, or a combination thereof. When the second layer 215 includes both the fine walnut shell particles and the sand, the fine walnut shell particles and the sand are preferably intermixed. FIG. 3 depicts illustrative infill 305 comprising a layer 310 of fine walnut shell particles and sand intermixed. In some embodiments, the layer 310 when installed consists essentially of fine walnut shell particles and sand, wherein at least 1% (and no more than 10% or preferably no more than 5%) by weight of the fine walnut particles in that layer 310 are walnut particles that have a seize size of 50 or smaller size particles.

As a precaution, the present description uses the word “may” in order to avoid an understanding that only the specific embodiments that are described are contemplated by the scope of the invention.

In some embodiments, as shown in FIG. 4, the infill 405 may comprise a layer 410 of sand and a layer 415 of walnut shell particles of two different particle size ranges. The layer 415 of walnut shell particles may comprise walnut shell particles A in a first particle size range and walnut shell particles B in a second particle size range that is different from or includes at least some smaller particles than the first particle size range. The second layer 415 can include walnut shell particles that are in both ranges and are preferably intermixed. The walnut shell particles A in the first range may be considered as large particles whereas walnut shell particles B in the second range may be considered as fine particles. The two ranges can overlap, but the fine particles are preferably at least 2% by weight of the layer of walnut shell particles. In some embodiments, the layer 415 when installed consists essentially of the different size range walnut shell particles, wherein at least 1% (and no more than 10% or preferably no more than 5%) by weight of the different size range walnut shell particles in that layer 415 are walnut particles that have a seize size of 50 or smaller size particles.

In one illustration of embodiments, the infill may comprise a first layer of sand and a second layer of walnut shell particles (refers to crushed walnut shell particles). The second layer may include walnut shell particles in a first range of sieve-sizes from 8 to 50 (i.e., 2.38 mm-0.297 mm), preferably from 14 to 40 (i.e., 1.41 mm-0.420 mm), and more preferably from 14 to 30 (i.e., 1.41 mm-0.595 mm) The second layer may also include walnut shell particles in a second range of sieve-sizes from 30 to 200 (i.e., 0.595 mm-0.074 mm) and preferably from 50 to 100 (i.e., 0.297 mm-0.149 mm). In some embodiments, the second layer when installed consists essentially of walnut shell particles in the first range and walnut shell particles in the second range, wherein at least 1% (and no more than 10% or preferably no more than 5%) by weight of the walnut shell particles in the first and second range in the second layer are walnut particles that have a seize size of 50 or smaller size particles.

In another illustration, as shown in FIG. 5, the infill 505 may comprise a first layer 510 of sand and a second layer 515 of walnut shell particles and sand. The second layer 515 may include walnut shell particles C in a first range of sieve-sizes from 8 to 50, preferably from 14 to 40, and more preferably from 14 to 30. The second layer 515 may also include walnut shell particles D in a second range of sieve-sizes from 50 to 100, and preferably from 30 to 200. The amount of walnut shell particles C in the first range is preferably 70% or higher (e.g., 90%) by weight (e.g., of that layer) and the amount of walnut shell particles D in the second range is preferably 20% or lower (e.g., 2%) by weight (e.g., of that layer). The second layer 515 may further include sand E. The sand E may have a sieve-size in the range of 20 to 50 (i.e., 0.841 mm-0.297 mm). Thus, the second layer 515 may include walnut shell particles C, Din both ranges and sand E and are preferably intermixed. In some embodiments, the layer 515 when installed consists essentially of walnut shell particles in the first, second, and third range of sieve-sizes and sand, wherein at least 1% (and no more than 10% or preferably no more than 5%) by weight of the walnut shell particles in the first, second, and third range of sieve-sizes in that layer 415 are walnut particles that have a seize size of 50 or smaller size particles.

In the above embodiments, the infill 605, as shown in FIG. 6, may further comprise a third layer 520 of walnut shell particles or extruded composite. The third layer 520 may include walnut shell particles F in a third range of sieve-sizes that is different from or larger than the first range of sieve-sizes. Preferably, the third range is from 10 to 14 (i.e., 2.00 mm-1.41 mm). As noted, it possible that the range can overlap with the other ranges. The third layer 520 can provide a function such as to assist in cooling or temperature control.

In any of the embodiments described in this application, the walnut shell particles are preferably raw or untreated crushed walnut shells. For example, the preferred walnut shell particles are shells that have not been treated with anti-microbial additives. The walnut shells are preferably English walnut shells. Crushed walnut shells are shells produced by applying mechanical force to raw or untreated walnut shells to break raw or untreated walnut shells into smaller pieces of walnut shells. In some embodiments, raw or untreated walnut shells (not crushed) may also be used. Also in any of the embodiments described in this application, the first layer of sand is disposed closer to the backing of the artificial turf compared to the second layer of walnut shell particles or the second layer of walnut shell particles and sand. Also in any of the embodiments described in this application, the third layer of walnut shell particles is disposed further from the backing of the artificial turf compared to the second layer of walnut shell particles or the second layer of walnut shell particles and sand. Also in any of the embodiments described in this application, the first layer of sand may comprise sand having a sieve-size in the range of 20 to 50. The first layer of sand may also be known as a ballast layer or a stabilizing layer. Also in any of the embodiments described in this application, the first layer may be a layer made of material(s) that has characteristics or performance like sand or a layer made of sand and other material(s) that has characteristics or performance like sand. Also in any of the embodiments described in this application, each layer in the infill may have the same or different thicknesses, and the thickness may be modified to meet specific performances. For example, the first layer (the sand layer) may have a thickness between ⅛″ and ¾″, the second layer (the layer containing walnut shell particles only or both walnut shell particles and sand) may have a thickness between ½″ and 1½″, and the third layer (the layer containing walnut shell particles or extruded composite) may have a thickness between ⅛″ and 1″.

For example, referring to FIG. 7, the infill 705 may comprise a first layer 710 of sand F, a second layer 715 of walnut shell particles G, H and sand I, and a third layer 720 of extruded composite. In the first layer 710, the sand F may have a range of sieve-sizes from 20-50. The sand F may be disposed on the backing 725 of an artificial turf 730. In the second layer 715, the sand I may have a range of sieve-sizes from 20-50 and the walnut shell particles may have a range of sieve-sizes from 14-30 (particles G). The walnut shell particles includes shell particles that fall into sieve 50-100 size at 2.5% by weight of the second layer 715 (particles H). Thus, the second layer 715 may include walnut shell particles G, H and sand I and are preferably intermixed. The intermixed walnut shell particles G, H and sand I may be disposed on the first layer 710. In the third layer 720, the extruded composite may be disposed on the second layer 715. In some embodiments, the second layer 715 consists essentially of walnut shell particles G, H and sand I, wherein at least 1% (and no more than 10% or preferably no more than 5%) by weight of the walnut shell particles G, in that layer 715 are walnut particles that have a seize size of 50 or smaller size particles.

FIG. 8 provides an illustrative particle size distribution for crushed walnut shell particles for use in a layer above the sand layer. As shown, the significant portion of the particle size distribution is constituted by sieve sizes 14-30. It can include other sieve sizes. In particular it includes particles below 50 sieve at 2% by weight, which is described above. The inclusion provides enhanced performance.

In implementation, the turf system may typically also include the installation of pad that are position under the backing to provide additional shock absorption.

In any of the above embodiments, the illustrative weight percentages can mean approximate weight percentages, instead of exact weight percentages. The term approximate or about means ±0.5%, preferably ±0.2%, and more preferably ±0.1% of the illustrative weight percentage. For example, approximate or about 5% by weight means between and including 4.9% and 5.1% by weight.

Exemplary infills, artificial turfs, and turf systems are described for illustrative purposes. Further, since numerous modifications and changes will readily be apparent to those having ordinary skill in the art, it is not desired to limit the invention to the exact constructions as demonstrated in this disclosure. Accordingly, all suitable modifications and equivalents may be resorted to falling within the scope of the invention. Applications of the technology to other fields are also contemplated.

It should be understood that combinations of described features or steps are contemplated even if they are not described directly together or not in the same context.

It is to be understood that additional embodiments of the present invention described herein may be contemplated by one of ordinary skill in the art and that the scope of the present invention is not limited to the embodiments disclosed. While specific embodiments of the present invention have been illustrated and described, numerous modifications come to mind without significantly departing from the spirit of the invention, and the scope of protection is only limited by the scope of the accompanying claims. 

What is claimed is:
 1. An infill composition for artificial turf fields comprising: at least one layer of particles comprising walnut shell particles, the walnut shell particles include walnut particles that have a sieve size of 50 or smaller sized particles, and the walnut particles that have a sieve size of 50 or smaller sized particles are between about 1% and about 5% by weight of the walnut shell particles.
 2. The infill composition of claim 1, wherein the at least one layer is applied over a backing of an artificial turf field and is interspersed between artificial fibers.
 3. The infill composition of claim 1, wherein the infill is an organic infill that is without or is almost entirely without containing rubber or similar materials.
 4. The infill composition of claim 1, wherein the remainder of the walnut shell particles in the layer includes an amount of walnut shell particles in the 10-40 sieve range, wherein the amount of walnut shell particles in the 10-40 sieve range is 50% or higher by weight of the walnut shell particles.
 5. The infill composition of claim 1, wherein the at least one layer is made entirely from walnut shell particles.
 6. The infill composition of claim 1, wherein the walnut shell particles are raw or untreated crushed walnut shells.
 7. The infill composition of claim 1, wherein the walnut shell particles further comprise walnut shell particles in a first sieve range, wherein the walnut shell particles in the first sieve range include walnut shell particles larger than the particles having a sieve size of 50 or smaller.
 8. The infill composition of claim 7, wherein the amount of the walnut shell particles in the first sieve range is above 90% by weight of the walnut shell particles.
 9. The infill composition of claim 7, wherein the first sieve range is from 14 to
 40. 10. The infill composition of claim 7, wherein the walnut shell particles in the first sieve range and the particles between about 1% and about 5% by weight of the walnut shell particles are intermixed in the at least one layer.
 11. The infill composition of claim 7, wherein the at least one layer of particles further comprises sand.
 12. The infill composition of claim 11, wherein the particles between about 1% and about 5% by weight of the walnut shell particles, the walnut shell particles in the first sieve range, and the sand are intermixed in the at least one layer of particles.
 13. The infill composition of claim 1, wherein the particles between about 1% and about 5% by weight of the walnut shell particles are particles that have a sieve size from 50 to
 100. 14. The infill composition of claim 1, wherein the at least one layer of particles further comprising sand in a sieve size range from 20 to
 50. 15. The infill composition of claim 14, wherein the walnut shell particles and the sand are intermixed in the at least one layer.
 16. The infill composition of claim 1, further comprising a second layer of particles comprising sand overlaying a backing of an artificial turf field.
 17. The infill composition of claim 16, wherein the least one layer overlays the second layer.
 18. The infill composition of claim 17, further comprising a third layer of walnut shell particles or extrude composite, wherein the third layer overlays the least one layer.
 19. The infill composition of claim 18, wherein the walnut shell particles further comprise walnut shell particles in a first sieve range, and the walnut shell particles in the first sieve range include walnut shell particles larger than the particles having a sieve size of 50 or smaller.
 20. The infill composition of claim 19, wherein the walnut shell particles in the third layer are in a second sieve range that is different from the first sieve range. 